Firefox Release Notes

Release Notes tell you what’s new in Firefox. As always, we welcome your feedback. You can also file a bug in Bugzilla or see the system requirements of this release.

Firefox Release

December 18, 2015

Version 43.0.1, first offered to Release channel users on December 18, 2015

We'd also like to extend a special thank you to all of the new Mozillians who contributed to this release of Firefox!


  • Prepare to use SHA-256 signing certificate for Windows builds, to meet new signing requirement (1079858)

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